#define  _CRT_SECURE_NO_WARNINGS
#include<stdio.h>
int main()
{
	long t, c, s;
	float v;
	scanf("%ld %ld %ld", &t, &c, &s);
	v = (float)c / t;
	printf("%.0f", (s - c) / v);
	return 0;
}